This experiment was conducted at College of Agriculture, University of Sulaimany to study the effect of different levels of Flaxseed powder (FP) as a source of omega-3 on the on the weight muscles and Fat partitioning and distribution for carcasses of Karadi lambs.It used 20 male Karadi lambs, with an average live-weight of 28 ± 0.398 kg and 4-5 months. They were randomly distributed to 4 treatments. FP was supplemented at the levels of 3%, 6% and 9% compared with the control group for 88 days. At the end of the experiment 12 lambs were slaughtered after overnight fasting of feed. Carcasses were chilled for 24 h at 4°C. Then, several measurements of carcass characteristics were taken. The results showed: higher (p<0.05) weights of the individual weight muscles located in different carcass region (pelvic limb, dorsal region and thoracic limb) were observed in Flax seed powder supplementation treatments. There were significant differences (p<0.05) in the carcass fat, offal and total fat in half animal body partitioning and distribution among treatments. Also it is noticed that the results of these traits were various. It can be concluded that using Flax seed powder (FP) as a source of omega-3 supplementation was increased muscles weight and reduced of carcass fat . These results were led to improvement of efficiency of meat production in Karadi lambs.